1. Field of the Invention
The present invention generally relates to a connector and a method of manufacturing the same. More particularly, the present invention relates to a connector and the manufacturing method with low manufacturing cost.
2. Description of Related Art
In general, electronic devices are provided with connectors and openings for exposing the connectors. External circuits such as network lines or audio cables can be inserted into the openings and electrically connected to the connectors.
FIG. 1A is a schematic cross-sectional view of a conventional connector. FIG. 1B is a bottom view of the conventional connector in FIG. 1A. Referring to FIGS. 1A and 1B, the conventional connector 100 includes a substrate 110, a first conductive layer 120, a plurality of connecting terminals 130, a second conductive layer 140, a gold layer 150 and a plurality of solder balls 160. The substrate 110 has a first surface 112, a second surface 114 opposite to the first surface 112, and a plurality of through holes 116 connecting the first surface 112 and the second surface 114. The first conductive layer 120 covers an inner wall 116a of each of the through holes 116, a part of the first surface 112 adjacent to the through holes 116 and a part of the second surface 114 adjacent to the through holes 116. The connecting terminals 130 are disposed around the through holes 116. The second conductive layer 140 covers the connecting terminals 130 and the first conductive layer 120 to electrically connect the connecting terminals 130 to the first conductive layer 120.
In the prior art, to prevent the part of the second conductive layer 140 located in the through holes 116 from being damaged in subsequent process and causing reduction in electrical reliability, the gold layer 150 is used to cover the part of the second conductive layer 140 located in the through holes 116 as well as the connecting terminals 130. Furthermore, for ensuring a complete coverage on the part of the second conductive layer 140 in the through holes 116, the gold layer 150 extends from the through holes 116 to a part of the second conductive layer 140 on the second surface 114 and thereby forms gold rings G. The solder balls 160 are located over the second surface 114, and the solder balls 160 are connected to the part of the second conductive layer 140 exposed by the gold rings G.
In needing the gold layer 150 completely covering the part of the second conductive layer 140 in the through holes 116, the required amount of gold in the prior art is large, while the price of gold goes high and the manufacturing of the conventional connector costs a lot.
Moreover, in the prior art, each of the gold rings G and the corresponding solder ball 160 are close to each other to release more available layout area and improve layout density. Therefore, the solder material may contact the gold rings G in the formation of the solder balls 160. While, the phenomenon of solder wicking occurs as the solder material contacts the gold rings G, and the formed solder balls 160 become smaller or even disappear. Alternatively, the solder balls 160 need to be separated from the gold rings G to prevent the contact between the solder balls 160 and the gold rings G, and thus the pitch between the solder balls 16 can not be reduced.